Article
Engineering, Mechanical
Su-Hwan Go, Dae-Su Kim, Yeon-Gyeong Chae, Seok-June Chae, Eun-Ji Kim, Hyeon-Min Yu, Bum-Joo Kim, Seok-Jung Park, Joun-Ho Lee, Sahn Nahm
Summary: A 3.0 mol% of NaNbO3 seeds were used to align the grains of NKNS-SZ-BAZ thick films along the [001] direction, resulting in textured films with large Lotgering factors. The NKNS-0.02SZ-0.02BAZ thick film exhibited a R-O-T structure with a high proportion of R-O structure and nanodomains, showing excellent piezoelectric properties.
Article
Chemistry, Multidisciplinary
Qian Chen, Shuyao Cao, Wei Song, You Xie, Zhengxin Yan, Jie Xu, Feng Gao
Summary: High ZT is highly desirable for tungsten bronze structure material. The anisotropic thermoelectric properties of KSr2Nb5O15 were studied using first-principles calculations, and the results were consistent with experimental data. KSr2Nb5O15 textured ceramics prepared by reactive templated grain growth showed significant anisotropic thermoelectric properties, with much higher power factor along the 11c direction compared to the perpendicular to c direction. The mechanism of the anisotropy was also clarified. This research provides a basis for improving the thermoelectric performance of KSr2Nb5O15 ceramics.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Materials Science, Multidisciplinary
Andrey Tumarkin, Alexey Bogdan, Evgeny Sapego, Alexander Gagarin, Ludmila Ivleva, Igor Serenkov, Vladimir Sakharov
Summary: Planar capacitive structures based on (Sr,Ba)Nb2O6 relaxor ferroelectric thin films were successfully fabricated, demonstrating good nonlinear properties and high communication quality factors.
Article
Materials Science, Multidisciplinary
Qingbo Mi, Yanfei Huang, Weiling Guo, Dongyu He, Gengchao He, Longlong Zhou, Zhiguo Xing, Haidou Wang
Summary: Potassium sodium niobate ceramics are promising environmentally friendly piezoelectric ceramics with excellent electrical properties. Ceramic films prepared by physical vapor deposition and chemical vapor deposition are thin, while coatings prepared by thermal spraying are thicker but lack in-depth study on the relationship between thickness and mechanical and electrical properties. This article studies and discusses the relationship between the mechanical and electrical properties of coatings and their thickness using plasma spraying technology. Results show that optimal microhardness, residual compressive stress, dielectric, and ferroelectric properties are achieved when the coating thickness reaches 300 μm. This study provides a theoretical basis for the practical application of coatings.
Article
Materials Science, Ceramics
Kosuke Tsuji, Zhongming Fan, Sun Hwi Bang, Sinan Dursun, Susan Trolier-McKinstry, Clive A. Randall
Summary: In this study, Cold Sintering was applied to densify a Potassium-Sodium Niobate solid solution composition, resulting in ceramics with comparable dielectric and electrical properties as conventionally sintered KNN. TEM analysis revealed high density of line defects in grains and crystalline grain boundaries with faceted kinks, which limit the piezoelectric properties and hysteresis of the ceramics.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Chemistry, Physical
Hong Tao, Jie Yin, QingShuang Zong, Lin Zhao, Daji Ergu, Jian Ma, Bo Wu, Bo Ma
Summary: Lead-free potassium sodium niobate (KNN) ceramics exhibit remarkable performance and have great potential in various applications. This study focuses on enhancing the stability of electrical properties of KNN-based ceramics through the addition of Fe2O3. The results show that the addition of Fe2O3 helps maintain high ferroelectric, piezoelectric, and dielectric properties, while excessive Fe2O3 leads to deterioration. Additionally, increasing Fe2O3 content improves the stability of strain and piezoelectricity at different frequencies and temperatures. Overall, this work provides an effective strategy for optimizing the stability of electrical properties in KNN-based materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Engineering, Electrical & Electronic
Xile Geng, Yi Wang, Fei Shang, Guohua Chen
Summary: Dense niobate glass ceramics with a principal crystalline phase of KSr2Nb5O15 were obtained through melt-quenching and controlled crystallization technique. The research reveals that the dielectric constant and crystal phase content increase simultaneously with the crystallization temperature rising from 800 to 950 degrees C. The achieved recoverable energy density (W-rec) shows a continuous increase from 0.61 to 1.23 J/cm(3) (@500 kV/cm) with the increment of crystallization temperature from 800 to 950 degrees C. The glass ceramic obtained at 850 degrees C exhibits the supreme discharge energy density of 1.82 J/cm(3) (@ 700 kV/cm), power density of 192.8 MW/cm(3) and energy efficiency of 82%. These findings indicate potential applications of the acquired glass ceramics in the field of energy storage.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Lucile Vaschalde, Encarnacion G. Villora, Kiyoshi Shimamura
Summary: This study successfully prepared high-density and stable undoped KNN ceramics using an optimized low-temperature sintering process. It was found that the best performance can be achieved in K >= 40% compositions, contrary to previous assumptions. The results of this study demonstrate that the preparation process is the main factor for achieving high-performance undoped KNN ceramics.
INORGANIC CHEMISTRY
(2023)
Article
Engineering, Electrical & Electronic
Irem Bobrek, Ayse Berksoy-Yavuz, M. Yunus Kaya, Sedat Alkoy, M. Baris Okatan, I. Burc Misirlioglu, Ebru Mensur-Alkoy
Summary: The lead magnesium niobate (PMN) - lead titanate (PT) solid solution ceramics were produced in both textured and random forms, showing relaxor dominant behavior. Textured ceramics exhibited enhanced electromechanical properties, with a converse piezoelectric charge coefficient of 545 pm/V. The electrocaloric (EC) behavior of these ceramics showed a temperature change of around 0.5 K under an electric field of 60 kV/cm, with texture development resulting in anisotropy in the EC response.
INTEGRATED FERROELECTRICS
(2021)
Article
Engineering, Mechanical
Xianghua Zhan, Yancong Liu, Peng Yi, Xiaoli Yin, Changfeng Fan, Jia Ma
Summary: Texture parameters significantly affect the tribological properties, with the texture area ratio, width-depth ratio, and angular velocity being the most influential factors.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Roberto Koeferstein, Stefan G. Ebbinghaus
Summary: By adding LiNbO3 as a sintering aid, the sintering temperature can be reduced, grain growth can be improved, and high density ceramic bodies can be obtained. The addition of different amounts of LiNbO3 affects the phase transition temperature and microstructure. In contrast, using LiF as a sintering aid results in the formation of considerable amounts of secondary phases and lower relative density.
JOURNAL OF SOLID STATE CHEMISTRY
(2022)
Article
Chemistry, Physical
Miao Zhang, Haibo Yang, Ying Lin, Qinbin Yuan, Hongliang Du
Summary: This study proposes a synergistic optimization strategy to simultaneously enhance the dielectric breakdown strength and energy-storage performance of KNN-based ceramics. By tailoring the grain size and controlling the temperature range, the KNN-BNZ ceramics exhibited ultrahigh recoverable energy-storage density and efficiency. Various techniques confirmed the presence of polar nanoregions, which contributed to the excellent energy storage performance. This finding not only discovers novel KNN-based ceramics with exceptional energy storage properties, but also provides a remarkable design strategy for future lead-free dielectric ceramics.
ENERGY STORAGE MATERIALS
(2022)
Article
Materials Science, Ceramics
Michael J. Brova, Beecher H. Watson, Rebecca L. Walton, Elizabeth Kupp, Mark A. Fanton, Richard J. Meyer, Gary L. Messing
Summary: This study investigates the effects of composition and residual template particles on the electromechanical properties of CuO-doped PYN-PMN-PT ceramics, showing that textured compositions exhibit improved properties but must be sufficiently on the rhombohedral side of the morphotropic phase boundary.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Inorganic & Nuclear
Zoya A. Mikhaylovskaya, Elena S. Buyanova, Alexander Malkin, Alexey N. Korotkov, Nikolay S. Knyazev, Sofia A. Petrova
Summary: The Bi:SrMoO4 ceramic samples were prepared and their crystal structure, thermal expansion behavior, and electrodynamic characteristics were studied. The results showed that increasing the bismuth content and optimizing the grain orientation have the potential to enhance the properties of Bi:SrMoO4 ceramics.
JOURNAL OF SOLID STATE CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Hao-Cheng Thong, Alexis Payne, Jia-Wang Li, Yue-Yu-Shan Cheng, Jacob L. Jones, Ke Wang
Summary: The excellent piezoelectric properties of lead-free potassium sodium niobate (KNN) ceramics have been reported in the past 15 years, but the poor reproducibility of these properties has hindered industrial development due to a lack of understanding of processing aspects. Chemical inhomogeneity during processing is a critical challenge for KNN-based ceramics, as their properties are strongly dependent on composition. In this study, in-situ temperature-dependent X-ray diffraction and thermogravimetric analysis were used to investigate chemical reactions during solid-state synthesis, revealing that chemical homogeneity is sensitive to reactant competition, explaining the chemical inhomogeneity in KNN and other lead-free piezoelectric ceramic systems prepared via solid-state synthesis.
Article
Materials Science, Ceramics
Sinan Dursun, Ebru Mensur-Alkoy, Mustafa Unsal Unver, Sedat Alkoy
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2020)
Article
Materials Science, Multidisciplinary
Dixiong Wang, Sinan Dursun, Lisheng Gao, Carl S. Morandi, Clive A. Randall, Susan Trolier-McKinstry
Article
Engineering, Electrical & Electronic
Ayse Berksoy-Yavuz, Umut Savaci, Servet Turan, Sedat Alkoy, Ebru Mensur-Alkoy
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2020)
Article
Materials Science, Ceramics
Ayse Berksoy-Yavuz, Ebru Mensur-Alkoy, Emre Erdem, Sedat Alkoy
CERAMICS INTERNATIONAL
(2020)
Article
Physics, Applied
Ebru Mensur-Alkoy, M. Baris Okatan, Ecem Aydin, Yusuf Kilic, I. Burc Misirlioglu, Sedat Alkoy
JOURNAL OF APPLIED PHYSICS
(2020)
Article
Materials Science, Ceramics
Xuetong Zhao, Jie Liang, Jianjie Sun, Jing Guo, Sinan Dursun, Ke Wang, Clive A. Randall
Summary: The study presents a strategy to fabricate dense ZnO-based ceramics with controlled grain growth and thin grain boundaries using cold sintering process (CSP). By utilizing CSP, the sintering temperature of ZnO-based ceramics significantly decreases, and Bi-rich intergranular films can be observed along grain boundaries, leading to superior performances of the ceramics. This work demonstrates that CSP is a promising technique for designing new submicron-/nano-ceramics with improved electrical properties.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2021)
Article
Materials Science, Multidisciplinary
Namik Kemal Gozuacik, Mustafa Cagri Bayir, M. Baris Okatan, I. Burc Misirlioglu, Sedat Alkoy, Ebru Mensur-Alkoy
Summary: This study investigates the effects of La substitution on the temperature dependent properties of PZT 70/30 ceramics and the electrocaloric effect induced by an external electric field. Experimental data and simulation results suggest that the gradual slanting of hystereses and reduction of transition temperature in La-doped samples are caused by the formation of dipolar defect complexes. The findings provide insights into the mechanism of electrocaloric effect and its potential applications in La-doped PZT 70/30 system.
Article
Materials Science, Multidisciplinary
Huseyin Alptekin Sari, Namik Kemal Gozuacik, Mustafa Yunus Kaya, Ebru Mensur, Sedat Alkoy
Summary: Lead zirconate stannate titanate (PZST) and lead lanthanum zirconate titanate (PLZT) ceramics were studied for their energy density and field induced strain behavior, showing changes in polar state from ferroelectric to antiferroelectric to relaxor antiferroelectric to linear dielectric with compositional modifications. Among the PZST compositions, the highest releasable energy density was obtained from the antiferroelectric composition, while the PLZT compositions with relaxor antiferroelectric character had the highest releasable energy density values with higher efficiencies.
Article
Materials Science, Multidisciplinary
Muhammet Boz, Mustafa Yunus Kaya, Omer Ozdemir, Sedat Alkoy
Summary: In this study, a new alternative to overcome the limitations of the operating frequency range was proposed and developed. A hollow cylindrical piezoceramic transducer, polarized radially, was designed and constructed to operate in the longitudinal length extension mode. The closed end of the hollow cylindrical piezoceramics was used as a passive cap to achieve piston mode operation. Finite element analysis was used to optimize the dimensional requirements of the transducer. The transducer showed promising underwater electroacoustic performance.
Article
Materials Science, Multidisciplinary
Ezgi Yalcin, Merve Ankut, Sena M. Sungur, H. Ibrahim Turgut, K. Sueda Kar, Sedat Alkoy, Aykut Aykac, Muhammet Boz, Ecem Aydin, Namik K. Gozuacik, Ebru Mensur
Summary: This study designed, fabricated, and compared tonpilz transducers based on 60PMN-PT and PZT compositions for their underwater performance, finding that the 60PMN-PT ceramics have comparable performance with PZT in underwater applications, indicating the feasibility of using 60PMN-PT ceramics in active device applications.
Article
Engineering, Electrical & Electronic
Irem Bobrek, Ayse Berksoy-Yavuz, M. Yunus Kaya, Sedat Alkoy, M. Baris Okatan, I. Burc Misirlioglu, Ebru Mensur-Alkoy
Summary: The lead magnesium niobate (PMN) - lead titanate (PT) solid solution ceramics were produced in both textured and random forms, showing relaxor dominant behavior. Textured ceramics exhibited enhanced electromechanical properties, with a converse piezoelectric charge coefficient of 545 pm/V. The electrocaloric (EC) behavior of these ceramics showed a temperature change of around 0.5 K under an electric field of 60 kV/cm, with texture development resulting in anisotropy in the EC response.
INTEGRATED FERROELECTRICS
(2021)
Article
Materials Science, Multidisciplinary
Merve Nur Ciftci, Berk Degirmenci, Irem Bobrek, Sedat Alkoy, Aykut Aykac, Muhammet Boz, Ayse Berksoy-Yavuz, Ezgi Yalcin, Namik K. Gozuacik, Ebru Mensur
Summary: A mid-frequency Tonpilz transducer array was designed and analyzed using finite element method. The MPB composition with superior dielectric and electromechanical properties was chosen to achieve higher performance. The results showed that the PMN-PT-based array has comparable transmit performance and superior receive performance compared to PZT.
JOURNAL OF METALS MATERIALS AND MINERALS
(2022)
Article
Acoustics
Mustafa Yunus Kaya, Sedat Alkoy
Summary: In this study, a novel class V flextensional transducer (FT) was developed by assembling symmetrically convex ceramic and metal caps to form a seashell-like structure. The transducer displayed four distinct flextensional modes in addition to the main radial resonance mode in the frequency range of 1 to 200 kHz. Prototypical devices made from different lead zirconate titanate (PZT) compositions were compared in terms of underwater performance, and transmitting voltage responses (TVRs) above 50 kHz ranged between 120 and 135 dB (ref 1 mu Pa/V).
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2023)
Article
Acoustics
Namik Kemal Gozuacik, Mustafa Cagri Bayir, Ebru Mensur-Alkoy, Sedat Alkoy
Summary: Rare-earth element doping has significant effects on the structural and electrical properties of lead-free bismuth sodium potassium barium titanate ceramics, leading to changes in crystal structure and electrical behavior. Doping can increase relative permittivity, alter ferroelectric properties, and enhance field-induced strain levels, making the ceramics promising for digital actuator and high-energy-density capacitor applications.
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
(2021)
Article
Engineering, Electrical & Electronic
Sinan Dursun, Kosuke Tsuji, Sun Hwi Bang, Arnaud Ndayishimiye, Clive A. Randall
ACS APPLIED ELECTRONIC MATERIALS
(2020)
